Virtual Input/Output Memory Management Unit Within a Guest Virtual Machine

摘要

A virtual input/output memory management unit (IOMMU) is configured to provide a firewall around memory requests associated with an input/output (I/O) device. The virtual IOMMU uses data structures including a guest page table, a host page table and a general control register (i.e., GCR3) table. The guest page table is implemented in hardware to support the speed requirements of the virtual IOMMU. The GCR3 table is indexed using a virtual DeviceID parameter stored in a device table.